Water-cooled guide shoe for piercing mills



Jne 17, 1941. H. E. ENGELBAUGH ETAL 2,245,655

WATER-000mm GUIDE sx-IQB Fon PIERCING MILLS June 17, 41941. z H. E. ENGELBAUGH :TAL 2,245,656 'l y wATER-coLEn G UIDE SHOE Fon PIERCING MILLS Filed sept. 27,' 1939 2 Sheets-Sheet 2 20, lK l H d INVENTORS aro/ En e/bau h and HerbergDav/Lsg l I zzn/nur.

a gxfmh Patented June 1.*7, 1941 WATER-000ml) GUIDE snoE Fort PIERCING MILLS Harold E. Engelbaugh, Youngstown, and Herbert i Davis, Poland, Ohio, assignors to The Youngstown Sheet and Tube Company, Youngstown, Ohio, a corporation of Ohio Application september 27, 1939, serial No. 296,748

(ci. sii- 51) 4 Claims.

This invention relates to the manufacture of seamless tubes and particularly to the billetpiercing stage of such manufacture.

The initial operation in the manufacture of seamless tubes is the forcing of a heated cylindrical billet over a piercer point carried on a mandrel and disposed -between the crossed rolls forming a piercer/mill. Guide shoes -are employed to direct the billet accurately onto the piercer point. It has been found that the shoes vused heretofore have a tendency to pick up scale to our invention, we maintain the guide shoes 'at a temperature such that scale and other particles do not tend to adhere or lbecome welded thereto. The building up of projections is thus prevented and the scratching and other marring of the billets is eliminated. `A preferred embodiv low castings.

ment of the apparatus comprises a. pair of op- .posed guide shoes having conduits formed therein for the passage of cooling fluid. Each shoe is mounted on a holder. A manifold in the holder communicates with the passages in the shoe and a. source of cooling fluid is connected to the holder.

The following detailed description of the embodiment above-mentioned refers to the accompanying drawings illustrating such embodiment. In the drawings,

Fig. 1 is a central, longitudinal, vertical section through the guide shoes of our invention and the supporting means therefor;

Fig. 2 is a transverse sectional view taken substantially along the plane of line II-II of Fig. 1 showing the piercer mill rolls diagrammatically; and

Fig., 3 is a sectional view taken substantially -i-.lnng the plane of line III-III of Fig. 1.

.Referring 'new in detail to the drawings, a piercer point l0 is mounted at the end of a .mandrel II supported in any convenient or knew-n manner at its opposite end. The point 4tion by clamps 23, 24, 23' and 24.

I0 together with crossed rolls I3 constitute a piercer mill of well-known -construction so it is unnecessary to disclose any further details thereof herein. A billet I4 heated to the :proper temperature is adapted to be pushed through an entering guide I5 and over the point I0 for piercing and expansion to a tube blank I6.

Opposed guide shoes I1 are mounted in spaced relation between the rolls I.3 and are shape'd and positioned as shown, to center the billet and direct it accurately onto the point I0. As shown in Fig. 2, the `opposed faces of the shoes are `of arcuate form.

The shoes I1 have cooling fluid passages I8 extending therethrough and open at each end thereof. T-hese passages may conveniently be formed by casting the shoes around lengths of pipe suitably positioned in a mold.

The shoes I1 are supported in holders I9 and I9. Each holder has a dove-tailed seat 20 near its entering end. The ends of the shoes I'I are inclined whereby they are adapted to cooperate with the seats 20 and dogs 2| for holding them against the seats. The dogs are pivoted as at 22 on any suitable or convenient support. As shown in Figs. land 2, the holders I9 are hol- They a-re supported 'm any desired manner, preferably on the housings .of the piercer mill, and are adapted to be fixed in posi- The clamps 24 and 24 engage the dogs 2|.

The holders I9 and I9' have longitudinal pasi sages 25 therein, each communicating with a transverse passage 26 formed in the face of the seat 20 and adapted to act as a manifold in supplying'cooling uid to the passages I8 in the shoes. A fluid-supply connection 2'I extends from each of the holders I9 and I9' to a suitable the conventional way to center the billet ac curately relative to the point I0. In addition, they exhibit a characteristic which is entirely novel, i. e., .freedom from the tendency to pick up scalel and othereparticles. The scratching and marrlng of the tube which has resulted from the building up of such particles on the shoes known heretofore is eliminated and the finished product is thus provided with a superior surface.

A further advantage of the invention is that the shoes -of my invention have a useful life about twice as long as the shoes used previously.-

The cost of the shoes, furthermore, is not materially greater than those now in use, 'I'he shoes may be of any suitable alloy. A typical alloy which has given very satisfactory results is comvposed of 22% chromium, 4% nickel, .6% molyb- 'uniform temperature throughout, thereby avoiding serious diii'erential thermal expansion and' contraction. Breakage of the guide shoes generally scores the piercer rolls and this causes marks on the surface of the pipe which may be sufficient to require their rejection when inspected. l

Although we have illustrated and described but a preferred form and practice of the invention, it will be recognized that changes in the structure and procedure disclosed may be made without departing from the spirit of the invention or the scope of the appended claims.

We claim:

1. Piercer mill guides for directing a heated billet onto a piercer point, said guides including opposed shoes adapted to be engaged by the billet and subject to heating by contact therewith, said shoes being cast from an alloy which is highly resistant to heat and abrasion, and having a plurality of cast-in conduits distributed across the billet-engaging faces of the shoes, means for supporting said shoes in spaced relation adjacent the pass of the mill, and connections for supplying cooling fluid to said conduits. whereby to maintain the shoes at substantially uniform temperature throughout and prevent spalling or breakage of the shoes resulting from differential thermal expansion and contraction thereof.

2. Piercer mill guides as deiincd by claim 1 characterized by shoe holders supporting the shoes adjacent the mill pass, and passages in said holders communicating with the conduits in said shoes.

3. Piercer mill guides as defined by claim 1 characterized by shoe holders supporting the shoes adjacent the mill pass, and a manifold in each of said holders communicating with the conduits in said shoes.

4. In a seamless pipe mill, opposed guides for directing a billet over a mandrel, said guides including shoes elongated axially of the mandrel, adapted to be engaged by the billet, and holders supporting. said shoes, said holders having seats against which the ends of the shoes abut, cooling-fluid passages in said shoes extending along said mandrel, and passages formed in said seats communicating with said first-mentioned passages. Y

HAROLD E ENGELBAUGH. HERBERT DAVIS. 

